{
	type Person = {
		name: string
		age: number
		gender: string
	}
	// 1. Partial 可选的
	type NPerson = Partial<Person>

	// 2. Readonly 只读的
	type ReadOnlyPerson = Readonly<Person>
	let p1: ReadOnlyPerson = {
		age: 18,
		name: '小花',
		gender: '女'
	}
	//
	// p1.age = 19  // 此处会报错，显示只可读


	// 3. Pick, 选一部分属性得到新的类型

	type PickPerson = Pick<Person, 'name' | 'age'>
}
